[edk2-devel] [PATCH 1/1] MdePkg/BaseLib: Fix invalid memory access in AArch64 SetJump/LongJump

[Jan Bobek]

Correct the memory offsets used in REG_ONE/REG_PAIR macros to
synchronize them with definition of the BASE_LIBRARY_JUMP_BUFFER
structure on AArch64.

The REG_ONE macro declares only a single 64-bit register be
read/written; however, the subsequent offset has previously been 16
bytes larger, creating an unused memory gap in the middle of the
structure and causing SetJump/LongJump functions to read/write 8 bytes
of memory past the end of the jump buffer struct.

Signed-off-by: Jan Bobek <jbobek at nvidia.com>
---
 MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.S   | 8 ++++----
 MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.asm | 8 ++++----
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.S b/MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.S
index 72cea259e9..deefdf526b 100644
--- a/MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.S
+++ b/MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.S
@@ -20,10 +20,10 @@ GCC_ASM_EXPORT(InternalLongJump)
         REG_ONE  (x16,      96) /*IP0*/

 

 #define FPR_LAYOUT                      \

-        REG_PAIR ( d8,  d9, 112);       \

-        REG_PAIR (d10, d11, 128);       \

-        REG_PAIR (d12, d13, 144);       \

-        REG_PAIR (d14, d15, 160);

+        REG_PAIR ( d8,  d9, 104);       \

+        REG_PAIR (d10, d11, 120);       \

+        REG_PAIR (d12, d13, 136);       \

+        REG_PAIR (d14, d15, 152);

 

 #/**

 #  Saves the current CPU context that can be restored with a call to LongJump() and returns 0.#

diff --git a/MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.asm b/MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.asm
index 20dd0f1b85..df70f29899 100644
--- a/MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.asm
+++ b/MdePkg/Library/BaseLib/AArch64/SetJumpLongJump.asm
@@ -19,10 +19,10 @@
         REG_ONE  (x16,      #96) /*IP0*/

 

 #define FPR_LAYOUT                       \

-        REG_PAIR ( d8,  d9, #112);       \

-        REG_PAIR (d10, d11, #128);       \

-        REG_PAIR (d12, d13, #144);       \

-        REG_PAIR (d14, d15, #160);

+        REG_PAIR ( d8,  d9, #104);       \

+        REG_PAIR (d10, d11, #120);       \

+        REG_PAIR (d12, d13, #136);       \

+        REG_PAIR (d14, d15, #152);

 

 ;/**

 ;  Saves the current CPU context that can be restored with a call to LongJump() and returns 0.#

-- 
2.28.0



-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#65726): https://edk2.groups.io/g/devel/message/65726
Mute This Topic: https://groups.io/mt/77195592/1813853
Group Owner: devel+owner at edk2.groups.io
Unsubscribe: https://edk2.groups.io/g/devel/unsub [edk2-devel-archive at redhat.com]
-=-=-=-=-=-=-=-=-=-=-=-